 
      CALL SEQUENCE...
       spplot  SPEC INPUT OUTPUT [ -t1    VAL1 -name VAL2 -a VAL3  -b VAL4  \ 
                                   -lv1   VAL5 -kind VAL6 -c VAL7  -d VAL8  \ 
                                   -label VAL9            -i VAL10 -j VAL11 ]
 
 
      DESCRIPTION...
       spplot - PLOTS A 2-D SPECTRUM
 
 
      AUTHOR  - N.E.Sargent, NOV 29/83.
      LAST REVISION: $Header: /home/cvs/RMNLIB/utils/rdiag/lspgm/spplot.ptn,v 4.10 2014/12/22 19:24:53 dugas Exp $
 
 
      PURPOSE - CONTOUR THE REAL PART OF A TRIANGULARLY TRUNCATED SPECTRAL
                FIELD IN FILE SPEC.  THE RESULT IS A 2-D SPECTRUM PLOT OF
                SPHERICAL HARMONIC COEFFICIENTS.
 
 
      INPUT FILE...
       SPEC = FILE CONTAINING THE SPECTRAL FIELD TO BE PLOTTED.
 
 
      INPUT PARAMETERS...
 
       NSTEP (t1)  = TIMESTEP NUMBER
       NAME        = NAME OF FIELD TO BE CONTOURED,
                     IF NAME='NEXT' OR BLANK, THE NEXT SPECTRAL FIELD IS PLOTTED
                     IF NAME= BLANK, NAME IS NOT CHECKED 
                     IF NAME='SKIP' THE NEXT SPECTRAL FIELD ON THE FILE IS SKIPPED
       LEVEL (lv1) = LEVEL NUMBER
       SCAL  (a)   = SCALING FACTOR FOR FIELD TO BE CONTOURED (0.0 DEFAULTS TO 1.0)
       FLO   (b)   = LOWEST VALUE OF SCALED FIELD TO BE CONTOURED
       FHI   (c)   = HIGHEST VALUE TO BE CONTOURED
       FINC  (d)   = CONTOUR INTERVAL
       KIND        = DETERMINES WETHER THE M.NE.0. PART OF THE FIELD IS TO
                     BE DIVIDED BY 2. AND/OR WETHER THE FIELD OR THE LOG
                     OF THE FIELD IS TO BE CONTOURED IN THE FOLLOWING WAY:
                     1) KIND.LT.0      THEN LOG10(FIELD) IS CONTOURED.
                     2) KIND.GE.0      THEN       FIELD  IS CONTOURED.
                     3) ABS(KIND).EQ.2 THEN DIVIDE THE M.NE.0 PART OF
                                        FIELD BY 2.
       MS    (i)   = IF MS .LT. 0 THEN PUBLICATION QUALITY PLOT IS PRODUCED
       IHEM  (j)   = CONTROLS INTERPOLATION FOR HEMISPHERIC DATA
                     DEFAULT IS ZERO; NO INTERPOLATION
 
       LABEL       = 80 CHARACTER LABEL FOR PLOT, (OMITTED IF NAME='SKIP').
 
       READ( 5,5010 ) NSTEP,NAME,LEVEL,SCAL,FLO,FHI,FINC,KIND,MS,IHEM
       READ( 5,5012 ) LABEL
 5010  FORMAT(10X,I10,1X,A4,I5,4E10.0,I5,1X,2I2)
 5012  FORMAT(A80)
 
 
      EXAMPLE OF INPUT CARDS...
 
    SPPLOT  79010100 TEMP 1000        1.        0.      300.       10.   -1 -1
    JANUARY FIRST PLOT OF LOG SCALE OF TEMPERATURE AT 1000MB
 
         0123456789012345678901234567890123456789012345678901234567890
         1         2         3         4         5         6         7
 
 
      EXIT CONDITIONS...
        0 NO PROBLEMS
        1 INCOMPLETE DIRECTIVE SET (NO LABEL CARD)
        2 UNABLE TO FIND A REQUESTED RECORD OF THE SAME SIZE AS FIRST
        3 SKIPPED TO EOF
        4 UNABLE TO READ SPEC
